[llvm] [AMDGPU] GCNRegPressure printing pass for testing. (PR #70031)

[Matt Arsenault via llvm-commits]

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@@ -487,3 +488,111 @@ LLVM_DUMP_METHOD
 void GCNRegPressure::dump() const { dbgs() << print(*this); }
 
 #endif
+
+static cl::opt<bool> UseDownwardTracker(
+    "amdgpu-print-rp-downward",
+    cl::desc("Use GCNDownwardRPTracker for GCNRegPressurePrinter pass"),
+    cl::init(false), cl::Hidden);
+
+char llvm::GCNRegPressurePrinter::ID = 0;
+char &llvm::GCNRegPressurePrinterID = GCNRegPressurePrinter::ID;
+
+INITIALIZE_PASS(GCNRegPressurePrinter, "amdgpu-print-rp", "", true, true)
+
+bool GCNRegPressurePrinter::runOnMachineFunction(MachineFunction &MF) {
+  if (skipFunction(MF.getFunction()))
+    return false;
+
+  const MachineRegisterInfo &MRI = MF.getRegInfo();
+  const LiveIntervals &LIS = getAnalysis<LiveIntervals>();
+  
+  auto &OS = dbgs();
+
+// Leading spaces are important for YAML syntax.
+#define PFX "  "
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arsenm wrote:

does a constexpr constant string work?

https://github.com/llvm/llvm-project/pull/70031